Can you please explain why every single fashion magazine is telling me to buy a pink coat this season?Ellie, by email

As Ellie has perceptively summed up in her plaint, it would be easier to bring about peace in the Middle East this autumn than to find a fashion magazine that is not pushing pink coats. It's strange, though, that no magazine has written about that pink coat at Marks & Spencer – OH, WAIT A MINUTE, yes they have, every single one, on every single page. My God, probably even Horse & Hound has done a fashion spread featuring various yearlings and west highland terriers all sporting that sodding M&S pink coat.

Whoever was in charge of promoting that coat, stick a fork in yourself because you're done. I don't think there has been such an efficient PR job in the fashion world since the time, earlier this year, that various fashion editors started insisting anyone who was still feeling insulted by John Galliano's antisemitic rant should really get over themselves because the poor guy was drunk, bless him, and he's now designing again and that's what really matters, yeah?

Regarding the M&S pink coat specifically, every season some high-street outlet – sometimes Whistles, sometimes Zara, occasionally M&S – will knock out a decent garment that happens to be quite similar to one seen on the runways. Fashion stylists will then burst their buttons with excitement – not from, ew, fatness, obviously – that they can now feature a piece of clothing which is designer-y, while at the same time fulfilling their harassed editor's brief that they have to use at least one garment in the fashion shoot that costs less than a month's rent. This season, it has been the turn of the M&S pink coat to be that garment, which is why that perfectly-nice-but-please-everyone-get-a-grip coat has been featured in every single blinking publication and continues to be so, even though it has long since sold out.

The reason fashion magazines have been excited over the M&S coat is because various high-end designers all made pink coats this season. Now, this kind of serendipitous synchronicity among designers does nothing to disabuse me of my belief that what we call "trends" are actually "evil plots cooked up by designers who scheme together ahead of time to make similar colours and clothes to convince the public that in order to look up to date we need to buy their wares." And when the trend that season is a pink coat, that pretty much puts the wax seal on my suspicion.

A pink coat at the Osman show. Photograph: Tim P Whitby/Getty Images

Has there ever been a more perfect trend for fashion retailers than a pink coat? Coats are the one type of clothing that everyone accepts should be expensive. Even chaps who gasp in horror at shoes that cost more than £50 will unblinkingly pay over £200 for a coat, because a coat is something that needs to be good quality: it needs to be warm, it ideally should be waterproof and it needs to withstand daily wear. Ergo, expenditure is acceptable.

Let us look again at the pink coat. Pink coats are, quite clearly, ridiculous. No female over the age of seven, other than Barbara Cartland, has ever wanted to wear a pink coat every day, if at all. Even I don't want to wear a pink coat, and I own three feathered alice bands. That's how impractical and girly pink coats are. A coat is your armour, something you can slip on and, if you want, render yourself invisible. If you run out to the newsagent in the morning for some emergency Marmite and a newspaper, no one will notice that you're still in your pyjamas, because your coat is protecting you. A pink coat does not offer that kind of protection. To be honest, a pink coat kind of looks like a nightie, which renders the disguise null.

Certainly, there is space in one's life, and sometimes one's cupboard, for an Occasion Coat. I have an Occasion Coat – I wear it to fancy restaurants and weddings in the winter, and it's the same one I've had for almost a decade. I only wear it a few times a year, but those times tend to be quite windswept and wet, because you know what? It's a coat, which means I wear it when it's cold, and because I live in this country and not Malibu, it is often windy and wet when it's cold. Yet my coat still looks grand, 10 years on.

You know what wouldn't look clean after a bit of rain? A pink coat. In fact, after just one day the pink coat would probably be a smudgy lilac coat, and after one more day it would be a sludgy grey coat. And if by some miracle you didn't get your coat dirty, you'd still have to get a new one next year to stop all the annoying people coming up to you and banging on about how last season you are. Being "last season" doesn't matter a jot, but it is extremely irritating to be told 10 times a day you are.